The head of the Association of School and College Leaders has hit back at employers' complaints that school leavers lack basic skills, and blamed them for the drop in pupils taking language GCSEs.

Despite a record number of pupils receiving top grades in their GCSEs today, employer bodies and some unions have voiced fears that many school leavers lack the numeracy, literacy and communication skills to survive in the workplace.

But John Dunford, ASCL general secretary, said the 20-year record of year-on-year improvement in GCSE results was a cause for celebration and "a record of which any British company would be proud".

He said employers must bear a substantial responsibility for the fall in modern language numbers.

"Until they [employers] send out a much stronger message to young people that languages are important in the job market, GCSE numbers will continue to be low and British industry will continue to struggle to compete in a global market," he said.

Results released by the Joint Council for Qualifications (JCQ) today showed an overall increase of 0.9% - to 63.3% - in the number of A* to C grades awarded across all subjects in England, Wales and Northern Ireland.

But employers and unions are calling for urgent curriculum changes to prevent 16-year-olds leaving school without basic numeracy, literacy and communication skills.

The Federation of Small Businesses and the British Chambers of Commerce have both demanded urgent reforms to secondary education. The Institute of Directors said 54% of its members believed skills had got worse over the past decade, compared to 24% who thought they had improved. Meanwhile, Mary Bousted, general secretary of the Association of Teachers and Lecturers, said GCSEs continue to fail pupils.

The JCQ said entries in English, maths and science were up this year, accounting for 46.4% of the full course GCSE entries. The grades pupils received in these subjects rose too.

There were 1.5% more entries for English - 732,293 in 2007 - and 0.6% more grades A* to C (62.2%). In maths, there were 1.3% more entries (760,299) and 0.9% more grades A* to C.

Overall, science entries were up and more pupils took individual science subjects this year. Entries in biology rose by 5.2% to 63,208, chemistry by 4.3% to 59,219 and physics by 4.2% to 58,391.

The subjects with the highest A* to C grades were chemistry (90.9%); physics (90.6%); biology (88.9%); classics (88.4%) and other modern languages (82.9%).

There was a 2.2% rise in the number of entries for the single science GCSE (98,485), but the numbers taking double science GCSE dropped by 0.4% to 956,056 this year. This is because of a significant drop in entry for ICT, which fell from 44,554 in 2006 to 27,656 this year.

But the largest falls were in modern languages. German entries were down by 10.2% to 81,061 and French down by 8.2% to 216,718. The pass rates rose, however: up 2.1% at grades A* to C in German and by 1.8% in French.

Spanish entries also rose by 3.0% to 63,978 and other modern languages rose 5.5% to 30,794.

The figures showed an overall percentage drop in candidates getting grades A* to G from 98.1% last year to 98.0% in 2007.

The gap in achievement between boys and girls narrowed slightly, with 1.2% more boys achieving A* to C grades than last year, compared with 0.6% more girls.

Jim Sinclair, JCQ's director, said: "The improvement in the GCSE results this year is testament both to effective teaching and the dedication and hard work of students. There are positive signs overall, with increased entries in mathematics and science, and the performance in all subject areas is improving."

Schools minister Jim Knight said GCSEs remained "robust, rigorous and respected and a vital stepping stone to life to further study and employment".

He added that the new diplomas, expanding apprenticeships and skills training and raising the education and training age to 18 would address employers' needs.

He said the government's long-term measures would increase the number of people studying languages "at GCSE, A-level and beyond", but said making the study of languages compulsory at GCSE "simply does not motivate pupils"- a view backed by Lord Dearing, the government's favourite education troubleshooter, who authored several landmark reports.

Lord Dearing said: "We need to engage from an early age and spark an enthusiasm in languages... and make languages compulsory in primary schools and radically more interesting for learners."

He said a return to mandatory language teaching at age 14 would not motivate those who find languages difficult or produce quality linguists.

Mike Cresswell, director general of the Assessment and Qualifications Alliance, said: "People who do [languages] get better than average GCSE results. But I don't think there are signals coming from the employment market to the effect that people coming with a modern language qualification are very valuable."

Carole Whitty, deputy general secretary of the National Association of Headteachers, said more needed to be done to persuade people of the importance of learning another language. "The strategy of teaching languages in the primary schools should eventually make a difference to the GCSE profile of results."

She called employers' complaints over lack of skills in school leavers "tired and tiresome comments".

"Of course the basics are important and schools will continue to work hard on them. However it is also important to note that we are in the midst of a technology revolution and this generation of 16-year-olds is probably one of the most usefully skilled groups of young people we have ever had. Businesses should be using these highly skilled 21st century communicators to transform their businesses, not alienating them by criticising their success," she said.

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